package com.dzx.design.structural.proxy.dynamicproxy;

import com.dzx.design.structural.proxy.db.DataSourceContextHolder;
import com.dzx.design.structural.proxy.staticproxy.Order;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

/**
 * @author dzx
 * @ClassName:
 * @Description:
 * @date 2019年08月09日 10:18:59
 */
public class OrderServiceDynamicProxy implements InvocationHandler {

    private Object target;

    public OrderServiceDynamicProxy(Object target) {
        this.target = target;
    }

    public Object bind() {
        Class<?> aClass = target.getClass();
        return Proxy.newProxyInstance(aClass.getClassLoader(), aClass.getInterfaces(), this);
    }


    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        Object argObject = args[0];
        beforeMethod(argObject);
        Object object = method.invoke(target, args);
        afterMethod();
        return object;
    }

    private void beforeMethod(Object obj) {
        int userId = 0;
        System.out.println("动态代理 before core");
        if (obj instanceof Order) {
            Order order = (Order) obj;
            userId = order.getUserId();
        }
        int dbRouter = userId % 2;
        System.out.println("动态代理分配到【db" + dbRouter + "】处理数据");
        //设置数据源
        DataSourceContextHolder.setDBType(String.valueOf(dbRouter));
    }

    private void afterMethod() {
        System.out.println("动态代理after code");
    }
}
